Inlet manifold for internal-combustion engines



Jan. 1, 19 4- 1,479,168

R. W. A. BREWER INLET MANIFOLD FOR INTERNAL COMBUSTION ENGINES Filed Dec. 16 1919 2 Sheets-Sheet l Fx Qg. 1.

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ATTORNEY Jan. 1, 924 1,479,168

R. W. A. BREWER INLET MANIFOLD FOR INTERNAL COMBUSTION ENGINES Filed Dec. 16, 1919 2 Sheets-Sheet 2 1 324 4.

$111 us 1% Oz Patented den. 1, rest.

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EEMZFQLB non. ENTERNAL-GOMBUSTXON ENG-I Apptioetton fillet @ecemhcr 1t, 1919. serial Ito. 845,377.

To all whom it may comm:

Be it MIQWKI that I, Bonner W. A. Brewer, a citizen of Great Britain and a subject of the King. of Great Britain, residing at lindianapolis, in the county of Marion and State of Indiana, have invented a new and useful Inlet Manifold for Internal-Combustion Engines, of which the following is a specification.

The object of my invention is to produce a distributin manifold for multicylinder internal com ustion engines of such character that, especially at starting, unvolatilized liquid fuel will not pass into the cylinders.

Specifically, automatic se aration of the unvolatilized liquid from t e gas stream and the forcible association of such separated portions with and along a properly heated surface in such manner that such unvolatilized portions will he volatilized while the major portions of the as stream will not be unduly heated.

in t e operation of a multicylinder engins, when the several cylinders are suplied with an explosive mixture through a manifold, the closing of each one of the inlet valves produces a-rehound in the gas stream which, in the ordinary forms of manifold, operates (because of the form and relative arrangement of the passages of the manifold) to retard thefiow of the mixture to the cylinder which is, at the time, receiving, or to receive, the next charge. thereby reducing the charge which should dew thereto. A further object of my invention 1s, therefore, to so form the several passages of the manifold that the unavoidable hackward impulse will he directed in such manner as to assist, instead of retard, the flow to the next cylinder.

In the utilization of the so called low grade" fuels, a high degree of compression is necesse in order to cause explosion and consequent y ditficulty is experienced, in those periods of operation when low power is desi. because of the decrease of the volume of fuel entering the cylinder (resultin in low compression), or because of its di ution with air. A further object of my invention is, therefore, to provide simple .means by which an my invention involves the inert gas, as, for instance, nitrogen or gases exhausted from the engine, maybe introduced into the fuel stream as it passes to the cylinders during a period of low power development, said inert gas furnishlng suiiicient volume to in sure roper compression, and to reduce the possi ilit of attainment of certain critical con itions hereafter referred to.

Jim the utilization of such low grade" fuels, especially those high in kerosene, it has been found that, following ignition, in the usual manner, resultant pressure increases tend to produce what may he termed critical pressure or temperature conditions in the ignited charge which result in detonations following the primary explosion, which detonations produce undesirable 2 99 The accompanying drawings illustrate embodiments of m invention.

Fig. 1 is a plan in half horizontal section of a device embodying my invention Fig. 2 a section on line 22 of Fig. 1; Fig. 3 a section on line 3-3 of Fig. 2; Fig. 3 a view similar to Fig. 3, showing a modification; Fig. 4.- a section of another embodiment of my invention on line M of Figs. 5 and 6; Fig, 5 a section on line 5-5 of Fi 4; Fig. 6 a section on line 6-6 of Fig. 4i; ig. 7 an elevation, in partial vertical section, on line 77 of Fig. 8. of another embodiment of my invention; Fig. 8 a fragmentary section on line 8 8 of Fig. 7 Fig. 9 a section on line 9-9 of Fig. 7 Fig. 10 a vertical section of another embodiment of my invention and Fig. 11 a section on line 11-11 of Fig. 10.

Referring first to Fi 10 and 11, 20 indicates the primary inlet of my im proved manifold, said passage being formed at its outer end for attachment to a carbureter of any desired form, and being preferably forwardly flared, or conified, so that the inwardly flowing material from the carburetor may expand into a zone of lower pressure and the liquid-fuel absorptive capacity of the air-stream be thereby increased. Branching from passage 20 are two main distributingpassages 21, 21, the axes of which lie at an acute angle (on the side of passage 20) to the axis of passage 20.

In practice ll have found that satisfactory results are obtained when passages 21 are arranged at degrees from passage 20. but this is not to be understood as a limit. Satisfactory result are not obtained, however, when passages 21 lie at degrees or more from passage 20. The wall 22, which is at the junction of passages 21, lies across passage 20, and this wall should be heated to a temperature slightly above the volatilization point of the least volatile component which is to be used (in practice, with present day fuels, above centigrade), thus furnishing a limited and localized hot spot against which all liquid, or non-volatilized, portions of the material flowing in through passage 20 will directly impinge with considerable force before they can pass into either one of passa es 21. The heated area of wall 22, and t e temperature thereof, should, however, be suficientl limited to serve to properly heat the aforesaid non-volatilized components without materially raising the temperature of the fuel mixture considered as a whole because, in the event of raising the tem erature of the mixture as a whole, there would he an expansion of said mixture to such an extent as to undesirably decrease the mass of gaseous mixture which can be drawn into an engine cylinder during the suction stroke of "its piston and thus reduce the pressure to which such volume can be compressed durin the compression stroke.

lln order to eat the wall 22, ll associate it with a chamber 26. The passages 21, beyond the constrictions 21' lead to distributmg portions of a manifold as will appear from the description of the other figures on the drawings, said portions of the manifold being free from special heating arrangements so'that they will be considerably cooler than the heating zone or cham ber of which the wall 22 forms a art.

lit will be seen from the above t at as the fuel mixture enters the manifold, the unvolatilized portions of the mixture will be caused to impinge upon the heated surface of the wall 22', before reaching either one of the passages 21, and because this wall becomes coated with liquid, said liquid will become volatilized, more or less, and the lighter gaseous portions of the mixture will be insulated from the main effect of the hot wall, the liquid serving as an insulator.

Referring now to F igs. 1, 2 and 3, 200 indicates the inlet passa e of the manifold provided with a restrictlon 201, on the order of a Venturi tube, delivering tangentially into a vortex chamber 202 into which the incoming gases may ex and. The walls 220 of chamber 202 lie wit 'n a heating chamherv 203 having an exhaust 204i and an inlet passage 205 which may be connected to the exhaust manifold of the engine.

The vortex chamber 202 is provided with two opposite discharge eyes 206, which may be defined by low annular ridges 206. Each e e delivers through a passage 210 of the enturi type, into branches 250 leading to separate engine cylinders. The vortex chamber gradua ly contracts toward eyes 206 so that the mixture, first ex ending into the chamber, is then contracts to pass through an eye thereof. The eye of the vortex cha1nber, instead of being located at the center of the vortex, is located eccentrically and away from the tangential inlet passage so that it lies in a region of comparatively high pressure instead of being located, as is usually the custom in vortex chambers, in the region of lowest pressure. Each of the branches 250 is expanded, as it leads away from passage 210, and the passages diverge from each other at an acute angle.

Tn this form, the mixture coming from the carbureter passes through the constriction 201 and ex ands into the vortex chamber 202. The eavier non-volatilized components of the inixture are immediately thrown against and dragged along the walls of the vortex chamber while the lighter gaseous component passes to and through the eyes 206, the non-volatilized portions ultimately becoming volatilized and passing through said eyes. As the mixture passes through the. passages 206 it again expands (because of the increased volume of the passages) against the heated surface 211, and passes into branches 250.

Assuming that flow through the left hand lower passage 250 (Fig. 2) is stopped by the closing of the inlet valve of the cylinder ted by that assa e, it is apparent that there will be a re oun and reverse impulse. back through the passage and this will assist, instead of retard, the flow of the gas through the opposite eye 206 and into the upper right hand assage 250, which serves two cylinders. l/ hen the flow through the upper right hand passage 250 is checked by the closing of the associated inlet valve, the backward impulse will be transmitted through the eyes 206 to assist the flow into the upper left hand passage 250 (which serves two cylinders), and when flow through that passage is stopped the resulting impulse will assist the flow into the lower right hand passage 250.

lit will thus be seen that flow through any onset the branches 250 will be assisted, during the suction stroke of the piston of its cylinder, by the reverse impulse set up in a companion branch. llt will also be seen that, in this form, the puddle of liquid fuel, which may gather inv the lower part of the vortex chamber, will be projected oil from the point 202' and be again caused to impinge upon and be dragged along, the

garages heated wall of the vortex chamber, thus insuring a thorough "olatilization of all of the liquid.

In the l'rtype, such as illustrated in Figs. 10 and 11, the drop in pressure in the carburetor to the inlet valve, is primarily and practically solely due to the friction loss. There is, of course, immediately adjacent the inlet valve, a lower" pressure than at the heating chamber or at the carburetor, but this is a comparatively small difi'erenc'e due, as stated, to friction loss. It is essential, therefore, that the mixture having become substantially fixed in the mixing chamber, may be cooled -so that it issues into the manifold arms, through the constrictions 21'.

In the vortex type, the diderence in pressure between the carburetor and the inlet valve is greater than in the T-type because of the inertia efl'ect produced by thevortex chamber. the friction loss were increased by an added friction due to the loss of kinetic energy due to the vortex action. Consequently, the absolute pressures in the manifold beyond the vortex chamber are enough lower than the absolute pressure in the peripheral portion of the vortex chamber, where the mixture has been fixed by the application of heat under relatively high pressures, to permit that mixture as it issues from the eye of the vortex chamber to materially expand in the region of lower pressure. It will, of course, be understood that the desired difference in pressures, between the heating chamber and the region adjacent the inlet valve may be secured by proper eccentricity of the vortex eye and the passage immediately beyond the eye properl increased in cross section to permit the esired expansion.

Referring now to Figs. 4, 5 and 6, the passage 300 is to be connected with the carburetor and through constrictions 301 leads into the vortex chamber 302, the walls 320 of which lie within a heating chamber 303 having an exhaust 304 and an inlet 305i which-may be connected to the exhaust imanifold of the engine.

The eye 30,6 of the vortex chamber 302 is located eccentrically and leads through a comparatively thin wall, as indicated in Fig. 8, into an intermediate portion 310 of the manifold, said portion delivering through constrictions 310 to branches 350 which lead to the engine cylinders.

In this form, and in Fig. 3, I have shown the inner surface of the peripheral wall of the vortex chamber formed into transverse ripple ridges 320, which serve to agitate the liquid as it is dragged along the heated we:1 320, volatilization being thus facilitat In other words, it is as though In Figs. 7, 8 and 9 there is shown a construction similar to that shown in Figs. 4, 5 and 6. The primary inlet passage 400 leads through a constriction am into a vortex chamber 402 having a peripheral wall 420 and an eccentrically placed eye 406. The wall 420 is heated by a heating chamber 403. The eye 406 leads through a comparatively thin plate into an intermediate portion 410 of the inlet manifold, said portion delivering through constrictions 410 to the branches 450, which lead to the engine cylinders.

In this form the portion 410 of the inlet passage may be considered as composed of two arms which lie at an acute angle to each other, both being in a plane substantially parallel tothe plane of the vortex chamber so that reverse impulses in the passages of the inlet manifold do not tend to retard flow to the cylinder which is receiving the next charge.

Leading into the portion 410 of the manitold at the junction of the two arms, is a passage 50 through which an inert gas (such as gas exhausted from the engine) may be drawn into the cylinders, under the control of a suitable valve 51 when roper power development is to be decrease without decreasing the compression preceding an ex-' plosion.

In Fig. 0, the exhaust pipe 304: is rovided with a valveSOd by means of w ich the low of heating gases throu h the jacket or heating chamber 303 may be regulated.

In Fig. 4 l have shown a door or detachable cover 300, giving access to the exterior vortex chamber so that heat controlling members, such as a heat retaining or retarding material, may be laid against the wall to be heated, thereby determining the amount of heating of said wall. By this means, also, the exterior of the vortex chamber may be cleaned.

I claim as my invention:

1. An inlet manifold comprising a vortex chamber having. two oppositely arranged discharge eyes and a tangential inlet passage, heating means associated with said chamber, and a delivery passage leading from each eye, said delivery passage being bifurcated and the bifurcations lyin at an acute angle to each other in the elivery direction.

2. An inlet manifold comprising a vortex chamber having two oppositel arranged discharge eyes and a tangential inlet passage, and a delivery passage leading from each eye, said delivery passage being bifurcated and the bifurcations to each other in the elivery direction.

3. An inlet manifold com rising a liquidretaining vortex chamber avingmtwo oppositely arranged discharge eyes and a lying at an acute angle, l 125 tangential inlet passe e, heeting meene associated with said 0 ember, end e delivery passage leedin from each eye.

4:. An inlet manifold com rising at liquidretaining vortex chamber eving two oppositely arranged delivery eyes, and a. tangential inlet passe e, and e delivery pee sage lending from enc eye.

5. An inlet manifold comprising a vortex 1 chamber, having an discharge eye and en iii-- r eve ilee let palssee, and e loifnted delivery pesse'ge leaning from said eye the bifurcations lying at anecute engle'to each other in the direction of delivery flow.

In witness whereof, I heve l'iereunto eet my hand at Indianapolis, Indiana, this third day of December, A. 1). one thond nine hundred and nineteen. 7

ROBERT W. A. BREWER. 

